Preparation And Performance Optimization Study On Thermostable Poly (Aryl Ether Sulfone Ketone) Ultrafiltration Membrane

In order to improve the poor thermal stability of the polysulfone (PSF)ultrafiltration membrane, which can not be used under the high temperature, as well asthe poor flexibility, bad solubility and the monomer is not easy to obtain of the poly(phthalazinone ether sulfone ketone)(PPESK) ultrafiltration membrane. In this paper,we discuss the synthesis of a novel high temperature material——poly (aryl ethersulfone ketone)(PAESK) by introducing two bisphenol monomers, and use it to preparethe ultrafiltration membrane. We can obtain the membrane with good comprehensiveproperties, especially the excellent thermal stability, so that be used for separation underhigh temperature condition.In this paper, by adjusting the molar ratio of bisphenol A (BPA) and9,9-bis(4-hydroxyphenyl)fluorene (BHPF), a series of novel PAESKs were synthesizedfrom BPA, BHPF,4,4’-dichlorodiphenyl sulfone (DCS) and4,4’-Difluoro benzophenone(DFB) via the nucleophilic substitution polycondensation reaction that in the presenceof anhydrous potassium carbonate as acid-binding agent. And the copolymer structurecan be confirmed by FTIR and1HNMR. The relationship between polymerization timeand the molecular weight and viscosity determines the reaction time is6.5h, which canobtain the copolymer with high molecular weight and moderate viscosity. Thecopolymer with excellent thermal stability when the molar ratio of BPA and BHPF is1to2by analyzing the thermal properties of the copolymer. The Tgof this copolymer isup to295℃, and the temperature at the weight loss of5%and10%are514.60℃and532.70℃, respectively. These copolymers have good solubility in common organicsolvents.The white, flexible and non-transparent PAESK ultrafiltration membranes areprepared via immersion precipitation phase inversion method, using poly(vinylpyrrolidone)(PVP) as additive and N,N-dimethylacetamide (DMAc) as solvent,by adjusting the proportion of different components of the casting solutions, the volatiletime, the coagulation bath temperature and the other process parameters. Through theexperiment of pure water flux, bovine serum albumin interception rate, water content,contact angle and thermal performance test, the membranes display not only goodpermeable and hydrophilic properties, but also excellent thermal stabilities.